Arc-lamp.



F. ALEXANDER.

ARC LAMP.

APPLICAHON FILED DEC. 10, 1914.

INVENTOR Patented Oct. 15, 1918..

i it ATTORNEYS WIT/V588 8 5%;

UNITED STATES PATENT OFFICE.

FOCSANEANU ALEXANDER, OF NEW YORK, N. Y., ASSIGNOR '10 ALLISON & HADAWAY, A FIRM COMPOSED' OF JOHN W. ALLISON AND THOMAS HADAWAY, OF NEW YORK, N. Y.

ARC-LAMP.

. Specification of Letters Patent.

Patented Oct. 15, 1918.

Application filed December 10, 1914. Serial No. 876,391

To all whom it may concern:

Be it known that I FOCSANEANU ALEXAN- DER, a subject ofthe king of Roumania, re-

siding at New York, in the county and State of New York, have invented certain new and useful Improvements in Arc-Lamps, of which the following is a full, clear, and exact description.

The invention which forms the subject ,of my present application relates to are lamps, and in the embodiments herein specifically illustrated and described it is intended ,par-

ticularly. for photographic use, to provide without :danger of being put out of order.-

To these and other ends the invention consists in the novel features of construction and combinations of elements hereinafter described.

In its preferred form the invention comprises two or more electrodes (or carbons, as they are commonly termed, although they may be and often are made wholly or in part of other materials) carried by a movable plunger or piston and two or more carbons which are, by preference, carried by station ary holders. The carbons carried by the pis-' ton are in series with each other and with the stationary carbons. A suitable electromagnetic device, as for example a solenoid 'surroundin the plunger, is provided in series with t e carbons to shift the plunger (against gravity or sprin -tension) and thereby separate the movab e from the stationary carbons for the production of the arcs when current, either alternating or direct, is supplied to the lamp. This provision of one automatic feeding mechanism to regulate two or more arcs in series I consider the most important feature of the invention, as it makes, the apparatus simplen and more compact than is ordinarily possible in multiarc lamps.

Convenient and effective embodiments of the inventionare illustrated in the accompanying drawings, in which- Figure 1 shows in section a complete lamp yprovnling two arcs.

' 2, is a plan view of the lamp shown in Fig. 1, and Fig. 3 is a cross section on line 33.

The "rod or plunger 10, Fig. 1 is movable vertically through a central aperture in the insulating head 11 of the hollow vertical cylinder 12, the lower portion of which serves as a dash pot for the piston head 13 fixed to the bottom of the plunger or piston 10. At opposite sides of the head, and fixed thereon, are two standards 14, 15, passing through openings in the plate 16 carried on the bottom of the solenoid 17 which surrounds the plunger and is itself held in place by a support 18 to which it is fastened by ,tie-wires 19. This support is carried by the inner ends of the terminals 20, 21, but of course is either insulated therefrom or is made of insulating material so as not to form a short-circuit across the terminals. The standards 14, 15, are provided to guide the rod 10 and prevent rotary movement thereof, as will be readily understood. The lower part of the element composed of the head 13 and the rod 10 is made of magnetic material and the upper part of non-magnetic material, so that when the solenoid is energized the said element will be drawn up. For instance, the head and the lower part of the rod (sa up as far as the line 22) may be iron an the rest aluminum.

On the insulating" head or closure 11 are two laterally extending brackets 23, 24, having upwardly open spring socket-pieces or carriers 25, 26 for the lower carbons 27, 28, the said pieces being threaded in the brackets to permit independent vertical adjustment of the carbons carried thereby. Set screws 29, 30 are provided to secure the socket pieces in adjusted position.

On the upper end of the rod or plunger 10 and insulated therefrom is a transverse bracket 31, in the plane of the brackets 23, 24, and provided at its ends with vertical apertures to receive the u per carbons 32, 33, which are vertically a justable in said apertures and are held in adjusted position by set screws 34, 35.

Series-connections are. provided, whereby the arcs burn in series. For this purpose the terminal 20 is connected to "the end 36 of the solenoid winding, and the other end 37 of the latter is connected to the bracket 23, while the terminal 21 is connected by a wire 38 to the bracket 24.

The operation of the lamp will now be readily understood. The carbons being in place and in contact with each other, the terminals 20, 21 are connected with the source of current, whereupon current will flow through the carbons and the solenoid in series; for example, from the source (not shown) to terminal20, wire 36, solenoid-17, wire 37, bracket 23, carbons 27 and 32, bracket 31, carbons 33 and'28, bracket 24, wire 38, terminal 21 and thence back to the source of current. Being thus energized, the solenoid raises the plunger 10, thereby separating carbons 32. and 33 and drawing arcs between each upper carbon-and the cooperating lower carbon.. As the carbons are consumed the arcs lengthen, thereby cutting down the current throu h the solenoid and weakening the field o the solenoid. When this field becomes too weak to support its load (the carbons and other parts lifted by the solenoid) the plunger .10 descends until the increased current (,dueto the shortening of the arcs) gives the solenoid field suflicient strength to prevent further descent. Inthis waythe movableica'rbons (in the present case the upper carbons) are fed automatically downward as-they are consumed and arcs or; substantially constant length are maintained.

When the current is cut off and th lunger allowed'to descend it may be foun that one or the other of the upper carbons does not come into contact with the corresponding lower carbon. On closing the circuit again it may be found that the voltage impressed is not sufiicientto cause the current to jump the gap between the-two separated carbons, in which case the gap can be readily closed byscrewing u the socket piece (25 or 26) in its supporting bracket.

It is to be understood that the invention is not limited to the constructions herein specifically illustrated and described, but can be embodied in other forms without departure from its spirit.

What I claim is 1. In. an arc lamp for the purpose described, in combination, a pair of stationary carbon-holders, a stem movable downwardly by gravity, a single solenoid surrounding the stem and connected in series with said stationary carbon-holders to raise said stem against ravity, and a pair of movable carbon-hol ers carried by the stem and" fastened thereon and insulated therefrom but in electrical connection with each other, said movable carbon-holders being shifted toward the stationary carbon-holders solely by gravity and away from the same solely bythe said solenoid in series with the carbon-holders.

2. In an arc lamp for the purpose described, in combination, an upright tubular shell adapted to serve as a dash pot, ais- 65 ton fitted to work therein, a stein fix to below the insulating closure. and above the therein, a vertical ravity-actuated stem exsaid piston, extending upwardly through and out of said shell, and having one or more vertical guide rods, a solenoid mount-' ed above the piston and surrounding the stem to raise the same magnetically and havin a transverse baseplate at its bottom provi ed with one or more openings loosely fitting said guide rods to prevent rotation of the piston and stem, stationary lower carbon-holders mounted above the solenoid, carbon-holders carried by the said stem and movable therewith, and seriesronnections for the solenoid and carbon holders.

3. In an arc lam for the purpose de scribed, in combinatlon, an upright tubular shell having an insulating c'losure atits u per end, a piston fittedto work in said she I and. having .a stem extending upwardly through the insulating closure, a'solenoid pistonand surrounding the stem to raise the- ;same magnetically, stationary lower carbon-holders mounted on saidinsulating closure, upper carbon-holders carriedbfy the terstem and movable therewith, a pair 0 m'inal's fitted in the side of the shell for con nection with a source of current, a member fixed to the terminals and supporting the solenoid, and series-connections between the terminals. and the solenoid and. carbon- '95 holders. i i

4. In an. arc lamp for the purpose described, in combination, an upright tubular shell, a piston fitted to move vertically tending into the s ell and having its ihner end fixed to said piston, a carbon carrier fastened on the stem outside of said shell and having a pair of carbon-holders in electrical connection with each other but insulated from the stem,-a' pair of stationary carbon-holdersinsulated from each other, a. single solenoid surrounding the stem to raisethe same and having one terminal connected to one of said stationary carbonholders, means for connecting the other terminal of the solenoid to one terminal ofa. source of current, and means for connectingthe other stationary carbon-holder to the other terminal of the source; the lamp having but one solenoid and the carbon-holders being in series with' each other and with the one solenoid.

5. In an arc lamp for the purpose described, in combination, apair of carbonholders insulated from each other, a pair, of carbon-holders, in electrical connection with each other, a gravity-actuated Stein on which one ofsaid pairs of carbon-holders is fastened to permit movementthereof, toward the other. pair, .only as the stem descends by gravity, a dash pot associated with the stem to oppose the gravity-move ment of the stem and its carbon-holders to-- ward the othercarbon-holders; a single splenoid, surrounding the stem toraise the same solenoid and the four carbon-holders in seand thereby separate the pairs of carbonries. 10 holders, and having one terminal connected In testimony whereof I afllx my signature to one of the insulated carbon-holders; and in the presence of two subscribing witnesses means 'for connecting a source of current FOCSANEANU ALEXANDER. to the other terminal of the solenoid and to Witnesses: the other insulated carbon-holder Where M. LAWSON DYER,

by current is caused to flow through the S. S. DUNHAM. 

